非圆弧滑面滑坡中满足平衡条件的预应力锚索设计拉力的确定方法

近20年来预应力锚索广泛用于加固滑坡或高边坡,但在以往的设计计算中,为简化起见,对非圆弧滑坡预应力锚索的设计一般采用指定设计外力而根据力的投影来确定锚索根数,并认为锚索作用力以集中荷载作用在滑面上。实际上,由于作用在地面的荷载经滑体传递后发生了很大的扩散作用,不满足力及力矩的平衡条件,其公式具有一定的缺陷,因而不尽合理,甚至由于锚设置不当造成其超载受荷而发生破坏,引起严重后果。本文根据其受力特点采用Morgenstern-Price法的基本假定从平衡条件出发,导出了确定锚索设计外力的迭代算法公式,对工程实际具有较大的理论意义。

The Method for Determining the Designed Pulling Forces of the Prestressed Cable-ancors used for Non-circular Slip-surface Landslides under the Equilibrium Conditions

The prestressed cable-anchors have been used widely in the reinforcement of land-slides and high slopes in the recent twenty years.To simplify design of prestressed cable-anchors for non-circular landslides,the external forces are designated and the number of cable-anchors is determined according to the force shadows.The acting forces of cable-anchors are considered to concentrate on the slip-surface.Actually,they have been spreaded to the ground-surface through the slide-body and the force and moment equilibrium conditions cannot be satisfied.The equation is less than reasonable and leaves some defects to be overcome.There may even occur serious results of damages during overloading caused by improper setting of achors.This paper adopts the fundamental assumptions of the Morgenstern-Price Method according to the stressed conditions and deduces the iterative formula under the equilibrium conditions for calculation of assigned external forces of cable-anchors.This has great theoretical significance to engineering practices.